Advice
Product overview
Drug action
Trastuzumab is a recombinant humanised IgG1 monoclonal antibody that binds to HER2. The subcutaneous formulation (Herceptin SC 600 mg/5 ml solution for injection, Roche Products Limited) contains hyaluronidase as an excipient. This temporarily breaks down hyaluronan in the subcutaneous space, increasing the volume that can be administered.
Proposed therapeutic indications
An application for an extension to the product licence for a subcutaneous formulation of trastuzumab plus hyaluronidase as an excipient was filed with the European Medicines Agency in March 2012. The manufacturer's proposed therapeutic indications for the subcutaneous formulation of trastuzumab are the same as for the intravenous formulation. Subcutaneous trastuzumab should be used only in people with metastatic or early breast cancer whose tumours have either HER2 overexpression or HER2 gene amplification as determined by an accurate and validated assay (Roche Products Limited: personal communication December 2012).
Early breast cancer
Subcutaneous trastuzumab fixed-dose formulation is proposed as a treatment for HER2-positive early breast cancer (Roche Products Limited: personal communication December 2012):
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after surgery, chemotherapy (neoadjuvant or adjuvant) and radiotherapy (if applicable)
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after adjuvant chemotherapy with doxorubicin and cyclophosphamide, in combination with paclitaxel or docetaxel
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in combination with adjuvant chemotherapy consisting of docetaxel and carboplatin
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in combination with neoadjuvant chemotherapy followed by adjuvant trastuzumab therapy, for locally advanced (including inflammatory) disease or tumours over 2 cm in diameter.
Metastatic breast cancer
Subcutaneous trastuzumab fixed-dose formulation is proposed as a treatment for HER2-positive metastatic breast cancer (Roche Products Limited: personal communication December 2012):
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as monotherapy in people who have received at least 2 chemotherapy regimens for their metastatic disease. Prior chemotherapy must have included at least an anthracycline and a taxane unless these treatments are unsuitable for the person. People with hormone-receptor-positive breast cancer must also have had an inadequate response from hormonal therapy, unless these treatments are unsuitable for them
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in combination with paclitaxel in people who have not received chemotherapy for their metastatic disease and in whom an anthracycline is not suitable
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in combination with docetaxel in people who have not received chemotherapy for their metastatic disease
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in combination with an aromatase inhibitor in postmenopausal women with hormone-receptor-positive metastatic breast cancer that has not been previously treated with trastuzumab.
Proposed course and cost
The recommended dose of subcutaneous trastuzumab is 600 mg irrespective of the person's body weight. Each fixed dose is delivered by injection over a period of up to 5 minutes, every 3 weeks. No loading dose is required. In early breast cancer, treatment with subcutaneous trastuzumab should continue for 1 year or until disease recurrence, whichever occurs first. In metastatic breast cancer it should continue until progression of disease (Roche Products Limited: personal communication December 2012).
The manufacturer states that subcutaneous trastuzumab is expected to have a list price of £1222.20 per 600 mg fixed-dose vial (Roche Products Limited: personal communication December 2012). In people with early breast cancer, the estimated cost per course of treatment is £22,000 (assuming a full treatment course of 18 cycles per person). In people with metastatic breast cancer, the estimated cost per course of treatment is £21,022 (assuming a mean of 17.2 cycles per person [Roche Products Limited: personal communication December 2012]).